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101.
This study examined the effects of indoor gardening on socialization, activities of daily living (ADLs), and perceptions of loneliness in elderly nursing home residents. A total of 66 residents from two nursing homes participated in this two-phase study. In phase one, experimental group 1 participated once a week for 5 weeks in gardening activities while a control group received a 20-minute visit. While no significant differences were found between groups in socialization or perceptions of loneliness, there were significant pretest-posttest differences within groups on loneliness and guidance, reassurance of worth, social integration, and reliable alliance. The results also demonstrated gardening interventions had a significant effect on three ADLs (transfer, eating, and toileting). Phase two examined differences in the effects of a 5-week versus a 2-week intervention program. Although no significant within-group differences were noted in socialization, loneliness, or ADLs, the 5-week program was more effective in increasing socialization and physical functioning.  相似文献   
102.
A mortality study of workers employed between 1944 and 1977 at an electrical capacitor manufacturing plant where polychlorinated biphenyls (PCBs), chlorinated naphthalenes, and other chemicals were used was undertaken. Age, gender, and calendar year-adjusted standardized mortality ratios (SMRs) were calculated for 2885 white workers. Total mortality and all-cancer mortality were similar to expected in both males and females. Females employed 10 or more years had a significantly elevated SMR of 6.2 for liver/biliary cancer. Intestinal cancer was significantly elevated in females employed 5 or more years after PCBs were introduced (SMR = 2.2). In males, stomach cancer (SMR = 2.2) and thyroid cancer (SMR = 15.2) were significantly elevated. Although individual exposure assessment was limited, PCBs alone or in combination with other chemicals could be associated with increased risks for liver/biliary, stomach, intestinal, and thyroid cancer.  相似文献   
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104.
We report the synthesis of novel steroidal androgen receptor ligands comprising 11beta-alkyl-Delta(9)-derivatives of 19-nortestosterone. These compounds are structurally related to the antiprogestin, antiglucocorticoid, and antiandrogen drug mifepristone (RU486). Nortestosterone analogues bearing 11beta-octyl and 11beta-decyl side-chains bind tightly to recombinant AR protein (IC(50) = 6.6 nM and IC(50) = 0.8 nM), block AR dimerization, exhibit activity against LNCaP prostate cancer cells, and comprise partial AR agonists with low antiglucocorticoid activity.  相似文献   
105.
Purpose To determine the in vitro drug sensitivity of two non-small-cell lung cancer cell lines after treatment with the novel lipophilic camptothecin derivative, 7-tert-butyldimethylsilyl-10-hydroxycamptothecin (DB-67), to determine if topoisomerase I protein levels decrease after treatment with DB-67, and to assess the duration and extent of topoisomerase I modulation after DB-67 exposure, in order to provide information about drug resistance that may be useful in determining an appropriate dosing schedule for DB-67.Methods The growth inhibition of the non-small-cell lung cancer cell lines A549 and H460 after exposure to DB-67 was evaluated with the MTS assay. A549 and H460 cells were treated for various times with DB-67 and topoisomerase I levels were determined by western blot analysis. In addition, A549 and H460 cells were treated with DB-67 for 24 h and topoisomerase I levels were determined by western blot analysis daily for 1 week after drug removal.Results DB-67 inhibited the growth of both A549 and H460 cells grown in culture; the A549 cells were more resistant to the cytotoxic effects of DB-67 than H460 cells. Notably, A549 cells had approximately one-half the baseline topoisomerase I than H460 cells. Topoisomerase I protein levels significantly decreased after 8–18 h of exposure to DB-67. Both A549 and H460 cells treated with DB-67 for 24 h had only negligible amounts of topoisomerase I at the end of treatment. However, within 24 h of drug removal topoisomerase I levels returned to near baseline levels in both cell lines.Conclusions The decrease in topoisomerase I levels caused by DB-67 may represent a mechanism of resistance to this novel camptothecin derivative. Dosing DB-67 once every 48–72 h may maximize the interaction of the drug with topoisomerase I and should be considered as a potential dosing schedule in the preclinical and clinical development of this compound.  相似文献   
106.
OBJECTIVE: Anecdotal reports have suggested mood improvement in patients with bipolar disorder immediately after they underwent an echo-planar magnetic resonance spectroscopic imaging (EP-MRSI) procedure that can be performed within clinical MR system limits. This study evaluated possible mood improvement associated with this procedure. METHOD: The mood states of subjects in an ongoing EP-MRSI study of bipolar disorder were assessed by using the Brief Affect Scale, a structured mood rating scale, immediately before and after an EP-MRSI session. Sham EP-MRSI was administered to a comparison group of subjects with bipolar disorder, and actual EP-MRSI was administered to a comparison group of healthy subjects. The characteristics of the electric fields generated by the EP-MRSI scan were analyzed. RESULTS: Mood improvement was reported by 23 of 30 bipolar disorder subjects who received the actual EP-MRSI examination, by three of 10 bipolar disorder subjects who received sham EP-MRSI, and by four of 14 healthy comparison subjects who received actual EP-MRSI. Significant differences in mood improvement were found between the bipolar disorder subjects who received actual EP-MRSI and those who received sham EP-MRSI, and, among subjects who received actual EP-MRSI, between the healthy subjects and the bipolar disorder subjects and to a lesser extent between the unmedicated bipolar disorder subjects and the bipolar disorder subjects who were taking medication. The electric fields generated by the EP-MRSI scan were smaller (0.7 V/m) than fields used in repetitive transcranial magnetic stimulation (rTMS) treatment of depression (1-500 V/m) and also extended uniformly throughout the head, unlike the highly nonuniform fields used in rTMS. The EP-MRSI waveform, a 1-kHz train of monophasic trapezoidal gradient pulses, differed from that used in rTMS. CONCLUSIONS: These preliminary data suggest that the EP-MRSI scan induces electric fields that are associated with reported mood improvement in subjects with bipolar disorder. The findings are similar to those for rTMS depression treatments, although the waveform used in EP-MRSI differs from that used in rTMS. Further investigation of the mechanism of EP-MRSI is warranted.  相似文献   
107.
CONTEXT: Unintended pregnancy is associated with poor health outcomes for mothers and infants, and is indicative of gaps in family planning services. Conventional measures of pregnancy intendedness do not reflect the multiple factors affecting a woman's pregnancy-related intentions and attitudes. METHODS: Data collected between March 2002 and February 2003 from 701 women in a public family planning clinic and 671 women in a public prenatal clinic in New Orleans were analyzed to examine factors underlying intendedness (including attitudes toward pregnancy and motivations to achieve or avoid pregnancy). RESULTS: In factor analyses, variables measuring pregnancy intendedness were represented by a single latent factor, pregnancy desirability. For first pregnancy, variables that best captured desirability were those measuring happiness, effort in achieving the pregnancy, extent of looking forward to telling friends, whether the pregnancy was intended (i.e., came at the right time or later), and whether the woman wanted to have a baby with her partner. For last or current pregnancies that were second or higher order ones, they were happiness, pregnancy wantedness, effort in achieving the pregnancy, whether the pregnancy was planned and whether the woman wanted to have a baby with her partner. Among women younger than 18 at first pregnancy, happiness and whether a woman wanted a baby with her partner were the only items that captured pregnancy desirability. CONCLUSIONS: Future surveys on pregnancy intendedness could reduce the number of questions used to capture pregnancy desirability. This should help standardize surveillance systems and permit better assessment of trends in pregnancy desirability over time.  相似文献   
108.
Adenosine has been implicated as a proximate mediator of escape deficits in the learned helplessness paradigm, suggesting that neuronal overactivation-a typical precursor to adenosine release-precedes the inescapable shock-induced impairment (T. R. Minor, W. C. Chang, & J. L. Winslow, 1994). In the present experiments, glutamate (100 microg) injection into the rat frontal cortex produced a deficit in escape performance. Pretest treatment with the adenosine receptor antagonist caffeine (7 mg/kg ip) reversed the effect of glutamate when infused 1 hr. but not 72 hr, after glutamate injection. Finally, microinjection of 2-amino-5-phosphonovaleric acid (5 ng) into the frontal cortex prior to inescapable shock prevented the escape deficit. These findings are consistent with the involvement of N-methyl-D-aspartate receptor activation in the frontal cortex in the helplessness effect.  相似文献   
109.
110.
BACKGROUND: Studies have suggested that nonspecific nonsteroidal anti-inflammatory drugs may inhibit matrix biosynthesis by articular cartilage, thereby accelerating the progression of osteoarthritis (OA). OBJECTIVE: The objective of this analysis was to determine whether 1-year treatment with the cyclooxygenase-2-specific inhibitor celecoxib at up to twice the recommended and maximally effective dose for OA had any deleterious effects on OA progression by assessing radiographic changes in knee or hip joint morphology in patients with OA. METHODS: In a 12-month, multicenter, prospective, open-label trial, patients with OA of the knee or hip or rheumatoid arthritis received celecoxib at doses ranging from that recommended for the treatment of OA (200 mg/d) to twice the recommended daily dosage (400 mg/d). Available radiographs showing baseline and end-of-treatment status were analyzed using semiquantitative measures of index joint morphology in patients with mild to moderate OA. The morphologic scores were then subjected to mean change and shift-table analysis to determine the extent and rate of disease progression. RESULTS: A total of 2,327 patients (796 with OA of the knee, 1,531 with OA of the hip) were included. A subset of 344 patients (160 with OA of the knee, 184 with OA of the hip) had radiographs from both before and after 12 months' celecoxib treatment. One hundred forty-seven and 158 pairs of knee and hip radiographs, respectively, were available for analysis. These revealed that, with the exception of significant hip joint-space narrowing (P = 0.029), no evidence of disease progression with long-term celecoxib treatment could be detected. The observed increase in hip joint-space narrowing was small (0.14 units/y) (95% CI, 0.08-0.20), was observed prior to celecoxib exposure (by mean change or shift-table analysis), and was not dose related. CONCLUSION: These results are consistent with the hypothesis that long-term therapy with celecoxib does not accelerate progression of OA of the knee or hip.  相似文献   
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